Electromagnetic relay having separate make and break iinductance coils



United States Patent 3,Z9Z,1zZ ELECTRoMAGNETIC RELAY HAvING SEPARATE MAKE AND BREAK IINDUCTANCE CoILS Avg"sf Bei 3nd Jooez Efen, Liubliana, l ugoslavf3, as signo s fo v Insfffnf zo Elekffoniko in AufoInafiko, Liuhona, flgoSlavia, a cofpofafion of Y"goslavio Eied ocf. ZZ, 1965, sof. No. 500,8o (:lainls pfio fffy, a pfcfion YugoSvia, Nov. 12, 1904, 13,Z55/o4 8 (:!ainS. (CL 33s154) ou pfesent invention felatos to an electfoInagnetic fe lay of the type whefein a paif of Tnagnetizable feedS, oveflappingly extending ffofn op osite endS of a genefally cylindfical envelope consiSti lg at least in paft of nonITlagnetic and nonconductive Inatefia1 Such aS gla S, afe felatively displaceable llpon Selective enefgization of two of n1ofe inductance WindingS coiled afound the en velope.

The uSe of Tefnanently nagnetiZab1e feedS, e.g. as diS- closed in U.s. Patents Nos. 3,037,08S and 3,0S9 075, haS the advantage of allovVing a Shoft pIllSe to Witch the fe- 1ay into eit]1ef a cloSed of an open position of itS con tactS, eithef position being subsequently Inaintained vvith out addftional cuffent How onti1 the condition iS fevefSed by anothef polSe.

In pfiof oonSffuctions of thiS type, hovvevef, folative ly con1plex vvindfng a fangefnents and/of a pefInanent prefnagnetization of one of the feedS vvefe needed in ofdef to bfing aboot the desifed S itching action- Mofe ovef, the aII11)litIlde fange of the n1ake ond bfeak pulSeS yvaS Shafply lifnited by the need fof pfeventing the genefation of a pulSe lafge enough to deStfoy the pefnlanent fnagnetization of (ebg. in the oaSo of a diffefentially vvound indnctance coil) to pfevent ITlagnetic fevefSals vvhich vvould tend to fecloSe a paif of contactS iust sepafated by a bfeaking p11lse.

It iS, thefefofe, an obiect of o11f pfeSent invention to pfovide an iITlpfoved electfonagnetic felay of this chafactef in vvhich the afofeStated diSadvantageS afe avoided.

A Inofe pafticolaf object of ouf invention iS to pfo vide an eloctfoInagnetic felay having only tvvo ind11ctance coilS, one fof Inaking and one fof bfeaking, So affanged as to be opefative vvhen enefgized With pulSes of vvidely vafying anlplitudes.

These obiectS afe fealized, in confoffnity vvith ouf pfesent invention, by the pfoviSion of a fifst inductance vvinding vvhich iS coiled afound at leaSt a paff of each of the tVvo feedS, in cofflbination With a second ind11ctance winding coiled afoUnd a poftion of only one feed vvhile teffflinating shoft of the oveflapping e)(tfefflities of the two feedS. The two coils afe advantageously vvoUnd, in a Inannef knovvn pef Se, on the OUtSide of the envelope fo which they may be faStened, pufSuant to anothef featufe of ouf invention, by having tefn1inal tufns thefeof Soldefed onto the envelope itSelf,

The two feeds, of at leaSt one of thenT, afe suitably biaSed to nlaintain theif oveflapping extfenities Spaced apaft in the absence of nlagnetic attfaction. such Inagfletfc attfaction vVill cone into play vvhen the fifst vvind ing iS enefgiZed, owing to the fact that the tWo pof tionS of this winding nlagnetize tho feSpective feedS ifI aiding felationship So that theif conffonting ends afe of opposite polafity. When theSe endS aftfact each othef, the fefflanent InagnetiSff1 of the feedS fnaintainS the connection even aftef the contctc1oSing pLllSe haS diSappeafed. subSeqLlently, upon the paSSage of a plllSe of oppoSite polafity thfough the othef Winding, the Inagnetization of the feed en1bfaced by that Winding is fe vefSed So that the conffonting eXtfefflifieS now fepel each othof; thUS, the cifcuit is now opened.

The fnagnitude of the closing )I11Se need only be Suf 3,Z9z,1zZ Patenfed Dec. 13, 1 966 ficient to effect Substantial Satufation of the two feedS, it nTay, howevof, be fnany tiITleS lafgef vvithoUt advefse effect. The opening )111Se, convefSely, need only be tfong enough to ovofcofne the IT111tLlal attfaction of the feeds due to theif fen1anent Inagnetization; this pulSe, too, Inay fise to seyefal tiInes that n1inimUIn anlplitude vVithout affecting the feInanent n1agnetization of the otf ef feed, fe. of the one not enveloped by it, to an eXtent vvhich night lead to a feclosing of the cifcI1it, While the feedS could be biased into theif noffIlally open-ci CLlited position by inhefent feSiliency, vve pfefef to con nect theif n1I1tIlally fen1ote eXtfen1ities vvith fespective teffninal InefnbefS by Shoft intefposed leaf spfingS of electfically condoctive nlatefial So that the n1agnefizable n1atefial of the feedS (e.g, feffite) fnay be choSen independently of the fequifed biaSing fofce.

Although the two windingS could n1utually oveflap, af the expenSe of a S1ight incfeaSe in the Stfay flux Eeld of the bfeak vvinding if it vVefe to suffound paft of the n1ake Winding, We pfefef to diS ose the two windings in axially Spaced felationShip difectly on the wall of the envelope. ThiS envelope, in tofn, advantageously iS nned with an ineft (i.enonoxidizing) gas.

In a pafticI1lafly advantageouS en1bodin1ent, the oveflapping tipS of the feedS afe coated with a highly conductivo but nonnlagnetic contact Inetal intefdiffLlSed vvith the Inagnetizable Inatefial of the feeds- ThiS contact Inetal is pfefefably silvef, gold, of one of the elenlents of platinun1 gfoup Sflch as fhodinfn, Its pfesence, as iS knovvn, pef Se, iS designed to pfevent afcing and chattefing vvhfle inS fing a clean bfeak in feS onSe to felatively Smal1cifcUitopening puISeS. v

The invention vviIl be descfibed in gfeatef detail vvith fefefence to the accompanying dfaWing Whose sole ngufe inuStfates an electfofnagnetic felay accofding to the invention, Shovvn in aXial Secfion, along vvith associated cifcllitfy indicated diagfaInn1atically.

The felay shown in the dfavving compfiseS a tubu laf glaSS envelope 1 having Sealed'in conductofS 4 and 4 aXially eXtending into it ffom oppoSite ends. A paif of feInanently 1Tlagnetizable feffife feedS Z and Z afe Secufed to fespective teffninals, constituted by the innef ends of conductofS 4 and 4, by vvay of Shoft leaf S )fingS 3 and 3. 1eedS 2 and Z have oveflapping extfeInitfes 5 and 5 biased into a noffnal Spacedapaft position by the feSiliency of Spfings 3 and 3. These oveflaPping extfefnitieS afo coated with a highly conductive contact InetaL aS deScfibed above, Which is intefdiffI1Sed vvith the feffite fnatefia of the fespective feeds.

The intefiof of the hefn1etically sealed envelope 1 iS filled With a nonoxidizing atInosphefe, such aS a gaS n1ixtufe consiSting of nitfogen and 10% hydfogen by weight.

TWo windings 7 and 7 afe coifed afound the outef Sufface of tllbe l, the fifst Winding 7 eXtending ovef the fuH length of feed 2 and a ffaction of tho length of feed Z vvhefeaS the Second Winding 7 en1bfaces only a paft of the length of feed Z not enveloped by the vvinding 7. It vvill be noted that vvinding 7 teffflinateS Shoft of the oveflapping endS 5 and 5 of the feeds. vVinding 7 has teffninalS oo and of connected acfoss a soufce of contact-closing pulSeS hefe shown diagfaInmaticany aS a battefy 8 and a SWitch 9. vvinding 7 has its tefIninalS oo, and of) connected acfoSS a Sifflilaf soLlfce of contact opening pulSes fepfeSented by a battefy 8 and a SWitch 9. /S indicated by the deSigna tionS N, S and N, S, the polafity of the inagnetic HUx tfavefSing feeds Z and Z upon enefgization of Winding 7 is opposite the polafity of the n1agnetic nux induced in feed Z upon enefgization of vvinding 7.

vVindings 7 and 7 have tefIninal tufnS 7o, 7o and 7, 7Z So1deted onto the outer s11Tface of glass tube 1 So aS to bo he1d in poSition on that tube,

The Springs 3 and 3 adyanfageously consist of hard oned and teTlpefed carbon steel with a cafbon content of abont 0.8% to 1.1% by vveight. The Inagneticux path feprosented by the Teeds and the spTingS n1ay be satuTable upon application of a coefcive foTce equivalent to about 12003200 ampefetnrns per meter and, When thus Satufated, Inay be erIneated by a 1111x of appfox1- n1ately 1 to 1.7 ganSS.

The treatInent of the ferrite TeedS With the contact Inetal 5 of 5, e.g. silver, gold of rhodiufn, may be car- Tiod out by e1ectTodepoSiting this meta1 opon the eX- tTeInities of the heat-treafed reedS and thereafter Subjecting these feeds to a teTnperature of, say, 600800 C. for a peTiod of abont 'n1in11teS to tWo houTs.

CloSure of switch 9 fof a shoIt peTiod, e,g. 10 (sec., wi11 genera11y suffice to satufate the feedS 2 and 2 So that theif extTeInitieS 5 and 5 attTact each othe1 fo c1oSe the Inain oifcuit thfough tofInina1 1eadS 4 and 4. ThiS oondition iS IT1aintained by the Tenlanent InagnetiSn1 of the TeedS unti1 nlonlentaTy closure of Switch 9, fof a simHar interva1, TeverSes the Inagnefization of feed Z to open the oontacts. the contactS c1oSe appfoxin1ate1y 1 to 3 sec. after appHcation of tho Inaking pu1Se to winding 7 and open abont S0 sec. aftef pasSage of the bTeaking pu1se through Winding 7. NatoraHy, the switcheS 9 and 9 aTe Tep1e Sentative of tfanSistofS and other electfonic SWitching de vices conventiona11y 11sed in soch sySten1s.

The Te1ative inSonSitivity of ouT iITlpfoved re1ay to vaTiation iI1 pulSe aII1 )1itudeS Inakes it partico1ar1y uSe fu1 in any ciTouit in Wh1ch SeveTa1 Such Ielays aTe to be connected in caScade, i.e. vhoTein the Inake of bTeak Winding of one Te1ay 1ies in seTies With either a Inake winding of a bfeak winding of another fe1ay. ThuS, the re1ay Shown and deScTibed may be uSed in cross-baI svvitches of telephone exchangeS and SiIT1ilar insta11ations. It is a1so easi1y coInPatible With printed circ11itry, thankS fo itS con1pact oonStTuction.

1. A11 e1ectron1agnetic re1ay con1pTiSing a Sealed en ve1opo of genefaHy cyHndTica1 Shape; a 1 irst and a sec ond Teed of TeInanent1y n1agnetizable InateTia1 extend 1n SubStantia11y axiany Wit11io saio oovelope from op In a typica1 sySten1 of thiS natuTe,

posite endS thereof, Said TeedS having over1apping eX treIT1ities vvithin said enve1ope and being pfovided at their opposite eXtfen11tieS With tern1ina1S for connecting them in an extefna1 circI1it, at leaSt one of Said TeedS being Tesiliently biased for keeping Said oveT1apping eXtTen1i tieS Separated in the absence of n1agnetic attfaction; a first inductance winding coiled aTound at least paTt of the length of each of said Teeds; a11d aoecond inducfance vvinding coi1ed around a poftion of only ono of Said TeedS bllt tefIninating shoft of Said oveT1ap ing eXtTelT1itieS,

2. A Te1ay as denned in c1aim 1 WheTein Said Wind ingS are axiaHy Spaced ffom each othe1.

3. A Telay aS defined in c1a1m 1 Whefein said oveT- lapping eXtreInitieS aTe provided With confronting suT faceS having coatingS of h1gh1y conductive but nonInag netic contact n1eta1 intefdi1fuSed vith Said Inagnetizab1e mateTiaL l 4. A felay as denned in c1aiIn 3 WheTein said oontact Inetal is Se1ected froIn the group which conSiStS of si1vef, gold and ThodiuIn.

s. A Telay as defIned in olaim 1 Whefein Said windingS are coiled around Said enve1ope and have teTIni nal tI1fns soldefed onto saIne.

o. A Telay as denned in c1aim 1, furthef coInprising switch Ineans foT alternately connocting said vvindingS acroSS a SouTce of cuTTent With mutoa11y oppoSite di- Tections of polarization.

7. A re1ay aS defined in claim 1 WheTein each of Said reeds iS pTovided vvith a 1eaf spring connecting the opposifo extreTnity theTeof to the respective feTn1ina1 for biaSing Said over1apping oxtreInities into a SepaTated po Sition.

8. A Te1ay as defined in c1aiIn 1 WheTein said envelopo iS Hned With a nonoxidizing gaS.

Roferonces Cifed by fhe Exa!ninef UNITED STATES PATENTS 3,0S9,075 10/196Z Peek 20087 3,2SZ.083 5/1966 vVagar 20087 

1. AN ELECTROMAGNETIC RELAY COMPRISING A SEALED ENVELOPE OF GENERALLY CYLINDRICAL SHAPE; A FIRST AND A SECOND REED OF REMANENTLY MAGNETIZABLE MATERIAL EXTENDING SUBSTANTIALLY AXIALLY WITHIN SAID ENVELOPE FROM OPPOSITE ENDS THEREOF, SAID REEDS HAVING OVERLAPPING EXTREMITIES WITHIN SAID ENVELOPE AND BEING PROVIDED AT THEIR OPPOSITE EXTREMITIES WITH TERMINALS FOR CONNECTING THEM IN AN EXTERNAL CIRCUIT, AT LEAST ONE OF SAID REEDS BEING RESILIENTLY BIASED FOR KEEPING SAID OVERLAPPING EXTREMITIES SEPARATED IN THE ABSENCE OF MAGNETIC ATTRACTION; A FIRST INDUCTANCE WINDING COILED AROUND AT LEAST PART OF THE LENGTH OF EACH OF SAID REEDS; AND A SECOND INDUCTANCE WINDING COILED AROUND A PORTION OF ONLY ONE OF SAID REEDS BUT TERMINATING SHORT OF SAID OVERLAPPING EXTREMITIES. 